Armature-winding.



Y. SAKAI.

ARMATURE WINDING.

APPLICATION l ILED FEB. a. 1910.

1,1 56,71 1. Patented 001. 12, 1915.

4 SHEETS-SHEET l.

WITNESSES; INVENTOR @uosgazw'rw COLUMBIA FLANOGRAPH co.,wAsmNm'oN. 01 c.

.Y. SAKAI.

ARMATURE WINDING.

APPLICATION FILED FEB. 3. I910.

1,156,71 1 Patented Oct. 12, 1915.

4 SHEETS-SHEET 2.

WITNESSES:

lNgNTOR I fi BY (GHQ S SDJQM'M,

/ ATTORNEY COLUMBIA PLANDGRAPH cvqwAsmNa'roN, n. c.

Y. SAKAI.

ARMATURE WINDING.

APPLICATION FILED FEB. 3. 1910.

1 1 56,71 1 Patented 001;. 12, 1915.

4 SHEETS-SHEET 3. 4. W W

WITNESSES:

ATTORNEY EVENTQR Y. SAKAI.

ARMATURE, WINDING.

APPLICATION FILED FEB. 3. 1910.

1,156,711. Patented 001.12, 1915.

4 SHEET$-SHEET 4.

WITNESSES! INVEETOR comm-IA WRAP" CO..WASI1INGTON. D. c.

Inn STATES PATENT OFFICE.

YAsunIno SAKAI, or EAST PITTSBURGH, PENNSYLVANIA, AssIeNon To WESTING-HOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION or rENNsYL-'VANIA.

ARMATURE-WINDING.

Specification of Letters Patent.

Patented Oct. 12, 1915.

To all whom it may concern:

Be it known that I, YASUDIRO SAKAI, a citizen or the United States, anda resident of East Pittsburgh, in the county of Allegheny and State ofPennsylvania, have invented a newand useful Improvement inArmaturevvindings, of which the following is a specification.

My invention relates to armature windings for single phase alternatingcurrent electric motors and particularly to windings for motors that areadapted to be started as commutating motors and to run at full speed asinduction motors.

The object 01 my invention is to provide a winding for motors of thecharacter above indicated that shall be more simple and economical inconstruction than others heretofore provided and shall also beexceptionally eilicient in service.

Ithas heretofore been proposed to provide single phase alternatingcurrent motors with such armature windings that they may be started ascommutating motors, with one number of'field poles, and be operatedatfull speed as induction motors, with a smaller number of field poles.These windings have heretofore been provided with conductors thatconnect together points of normally equal potential when the'motor hasthe larger number of poles and operates as a commutating motor, and thatshort circuit portions of such windings when the motor has the smallernumber of poles and operates as an induction motor.

The present invention provides a winding inwhich no cross connectionsare employed between points of normally equal potential, but in whichthe proper circuits are provided for each condition of operation: thatis, for each number of field poles.

My invention is illustrated in the accompanying drawings, Figure 1 ofwhich is a diagrammatic view of the-circuits of a motor embodying thesame. Fig. 2 is a diagramatic view of the armature of the machine. Fig.3 is an enlarged diagrammatic view of a few 01" the coils of thearmature winding. Fig; l'is a plan view of two of the coils of'the'armature winding. Fig. 5

is a side view of the end portions of the coils of Fig. 4. Fig. 6 is anend View of the coils of Figs. 4 and 5, and'Fig. 7 is a diagrammaticview of a few of the coils of a modified form of the winding.

The external circuit connections of a motor in which the presentinvention may be conveniently embodied are illustrated diagrammaticallyin Fig. 1, the said motor comprising an armature l, and a field magnetwinding having two parts 2 and 3 that may be connected in parallelrelation by means of a controller 4. As illustrated, the controller 4comprises a plurality of stationary Contact terminals 5 and two sets ofmovable conducting segments 6, 7, 8, 9 and 10, the one set (6, 7 and 8)being located upon a broken position-indicating line a, and the otherset (9 and 10) being located upon another position-indicating line b.When the controller segments upon the line a engage the stationaryContact terminals 5, the circuits are connected for operation of themotor as a series motor, the two parts of the field magnet winding beingthen connected in parallel relation and in series with the armature. Thecircuit connections just described produce the larger number offieldpoles, which, in the case of the armature windings illustrated in Figs.2, 3 and 7, is eight. When the segments 9 and 10 of the controllerengage the stationary contact terminals 5, the armature l isshort-circuited by the segment 9, and the two parts of the field magnetwinding are again connected in parallel relation, but the part 2 isreversed with respect to the part 3, as compared with the relation ofthe said parts when the controller occupies the position a. Under theseconditions, the motor operates as an induction motor, the number offield poles being reduced to four in the case of the armature windingsof Figs. 2, 3 and 7.

- The armature of the motor comprises a core member 12, having aplurality of peripheral slots in which are located two windingscomprising, respectively, a plurality of formed coils l8 and 14. Thepitches of the coils of the two windings differ very materially, thepitch of the coils 14 being 1 much less than that of the coils 18. Thetwo sets of coils occupy the same slots in the armature core, theconductors of the coils l3 occupying the outer and inner portions of theslots, while the conductors of the coils 1 loccupy the intermediateportions thereof. Both sets of coils are connected, at one end of thearmature, through resistance leads 17, to the segments 15 of acommutator cylinder and, at the other end, they are connected to eachother by means of clips 16, or other suitable devices. In practice, theresistance leads 17 may not always be necessary. The coils of the twowindings that are connected together and to the same commutator segmentsoccupy different core slots and each coil 14 is located approximatelycentrally within the are or pitch of the coils 13 to which they areconnected. The arrangement of the connections of the coils, at thecommutator end of the armature, is such that the extremities of the mostremote side portions of the two coils are connected together, the leadsfrom the coils 14 crossing each other in order to efiect this result.The arrangement of the connections 16 is such that the two windings areconnected to each other at corresponding intervals, at their ends remotefrom the commutator segments. That is, the connected points of thearmature winding correspond to each other in several respects, namely,they are substantially the middle points 01": the coils, and they areadj acently located.

For the purpose of more readily explaining the invention, the machineillustrated in Figs. 2, 3 and 7 is provided with definite polarprojections though, of course, it will beunderstood that the inventionmay also be employed in machines having distributed field windings andhaving no polar projections. With the larger number of field poles, thatis, when the motor is started as a commutating motor, adjacent polarprojections are of different polarity. Under these conditions, theconductor 18 of one of the coils 13 (Fig. 3), and the conductor 19 ofone of the coils 14 are, at each instant, located in fields of the samepolarity, and, accordingly, they constitute parallel conductors for thecurrents traversing them are in the same direction. The conductor 20 ofthe coil 13 and the conductor 21 of the coil 14 are also located, ateach instant, in fields of the same polarity so that they, likewise,constitute parallel conductors for currents traversing them in the samedirection. As the two sets-of parallel conductors are connected togetherat their ends that are remote from the commutator, and as they aretraversed in opposite directions by currents, they constitute a singlearmature coil-when the motor has the larger number of poles and operatesas a commutator m0- tor. With the smaller number of field poles,adjacent polar projections constitute pairs of the same polarity, withthe result that the conductors 18 and 19, respectively, of the coils 13and 14 are, at each instant, located in fields of opposite polarity, sothat they constitute parts of a closed-circuit coil in which currentstend to flow in opposite directions. Likewise, the conductors 20 and 21,respectively, of the coils 13 and 14, at each instant occupy fields ofopposite polarity, and they, accordingly, also constitute aclosed-circuit coil. This condition, of course, exists in each pair ofconnected coils, and a closed-circuit secondary winding is accordinglyprovided, so that the motor may operate as an induction motor with thesmaller number of field poles.

Although the winding of Figs. 2 and 3 is a combination lap and wavewinding, the invention is not limited in its application to windings ofthat specific type or form but may be applied generally in connectionwith windings of any type.

In Fig. 7, the invention is shown as applied to a pure lap winding, theprinciples of operation being the same as those which were explained inconnection with the wind-, ings of Figs. 2 and 3, and the constructiondiiiers only to the extent of a different arrangement of the connectionsat the com mutator end of the armature to provide for the overlappingadjacent coils.

While the invention has been shown and descrlbed as employed in a motorthat starts as a series commutator motor, its application is not limitedto such specific conditions, as the same armature winding may also beemployed if the motor is started as a repulsion motor, or as any othertype of c0mmu tator motor. It may also be employed in direct currentmotors, and in motors in which the number of field poles is not chan ed.7

I c aim as my invention:

1. An armature for dynamo-electric ma.- chines having two windings eachcomprising a plurality of coils, the coils of the respective windingsbeing connected together in pairs both at their terminals and atintermediate points.

2. An armature for dynamo-electric ma.- chines comprising two windingseach consisting of a plurality of coils, the coils of the respectivewindings being connected together in pairs both at their terminals andat intermediate points, and the terminal leads of one set of coilscrossing each other.

3. An armature for dynamo electric machines having two windings, each ofwhich comprises a plurality of coils, the coils of the respectivewindings being different in pitch and interconnected at each end of thearmature.

4. An armature for dynamo-electric mo.- chines having two sets of coilsof different pitch corresponding points of which are connected togetheronly at each end of the armature.

5. An armature for dynamo electric mas chines having two windings eachof which comprises a plurality of coils, the coils of one winding beingrespectively connected at each end of the armature to, and locatedwithin the arcs subtended by, the coils of the other winding.

6. In a dynamo-electric machine, the combination with a field magnet inwhich the number of poles may be changed, of a com mutator and anarmature having windings the conductors of which are connected in pairsat both extremities, one end of each pair of conductors being connectedto a commutator segment, and the coils of the re spectivewindingsdiffering in pitch.

7. In a dynamo electric machine, the combination with a field magnet inwhich the number of poles may be changed, or a commutatorand an armaturehaving windings the conductors of which are connected in pairs at bothextremities to constitute parallel circuits with one number of fieldpoles and closed-circuit coils with the other number of field poles, theconnected conductors being located in different parts of the armature,and one end of each pair of conductors being connected to a commutatorsegment.

8. In a dynamo electric machine, the com ination with a field magnet inwhich the number of poles may be changed, of a commutator and anarmature having windings the conductors of which are connected in pairsat both extremities, the connected conductors being located in differentparts of the armature, one end of each pair of conductors beingconnected to a commutator 10. A11 armature for dynamo-electric machinescomprising a commutator cylinder and two windings each consisting of aplurality of coils, the coils of the respective windings being connectedtogether in pairs both at their terminals and at intermediate points,and the terminals being connected to the commutator cylinder.

In testimony whereof, I have hereunto subscribed my name this 28th dayof Jan,

YASUDIRO SAKAI. Witnesses:

HAnoLo B. GAYLOR, B. B. I-IINES.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, I). C.

